I think you may have misunderstood the nature of thrust. The only way the ground would give any assistance to an a/c taking off would be if the generated thrust were to 'reflect' back and provide extra upward moving air to assist the a/c. This would only happen at an angle of approaching 90 degs with the ground.
What can happen is a ground effect where downward moving air (created by the motion of the a/c) 'bounces' off the ground and impinges on the a/c fuselage, wings and tailplane to create extra LIFT. This, whilst a factor during take off is more apparent when landing and can cause an a/c to 'float' along the runway. It is the reason that most commercial a/c autopilots land 'firmly'. I seem to reacall a prototype Trident (first full autoland a/c) crashed due to this phenominum and the Rad Alt and pitch logic was altered to compensate.